U.S. patent number 4,898,669 [Application Number 07/206,105] was granted by the patent office on 1990-02-06 for vascular access device, in particular for purification treatments of the blood.
This patent grant is currently assigned to Claber S.p.A.. Invention is credited to Franco Tesio.
United States Patent |
4,898,669 |
Tesio |
February 6, 1990 |
Vascular access device, in particular for purification treatments
of the blood
Abstract
A vascular access device includes a case having a first
connection structured to couple with an end of a cut blood vessel
such as an artery, a second connection structured to couple with an
end of a cut blood vessel such as a vein, and access ports for
removal means and admission means to be connected into the blood
vessels. A valve is arranged in a rotating manner with two
positions defining two independent passages. In a first position
the valve establishes connection between the first connection and
one of the access ports and between the second connection and the
other of the access ports, respectively. The first position is apt
for performance of a blood purification treatment. In a second
position of the valve, one of the passages establishes mutual
connection between the connections and the other of the passages
establishes mutual connection between the access ports.
Inventors: |
Tesio; Franco (Pordenone,
IT) |
Assignee: |
Claber S.p.A.
(IT)
|
Family
ID: |
11173899 |
Appl.
No.: |
07/206,105 |
Filed: |
June 13, 1988 |
Foreign Application Priority Data
|
|
|
|
|
Jun 16, 1987 [IT] |
|
|
20908 A/87 |
|
Current U.S.
Class: |
210/232;
137/625.47; 210/240; 210/321.72; 210/424; 604/248 |
Current CPC
Class: |
A61M
39/0247 (20130101); A61M 39/0208 (20130101); Y10T
137/86871 (20150401); A61M 39/223 (20130101); A61M
2039/0258 (20130101); A61M 2039/0282 (20130101); A61M
2039/027 (20130101) |
Current International
Class: |
A61M
1/00 (20060101); B01D 013/00 (); A61M 005/00 () |
Field of
Search: |
;604/4,5,6,175,236,905,248
;210/232,321.72,321.73,321.74,321.75,321.76,321.77,321.78,321.79,321.8,321.81
;137/625.47 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Jones; W. Gary
Attorney, Agent or Firm: Steele, Gould & Fried
Claims
I claim:
1. A vascular access device, comprising:
a case designed to be grafted permanently in living tissue and
having a pair of connections for blood vessels, the connections
being structured to couple with respective ends of at least one cut
blood vessel, the case having an outer surface covered with a first
layer of damping material on which is arranged a second layer of
biocompatible material weldable to the living tissue;
a two-position valve removably housed in said case and a pair of
access ports for removal means and admission means for blood, the
valve being a rotary valve having two independent passages wherein,
in a first rotational angular position of the valve the passages
establish connection between a first of the connections and a first
of the access ports and between a second of the connections and a
second of the access ports, respectively, and in a second
rotational angular position of the valve the passages establish
connection between said first and second connections and between
said first and second access ports, respectively, said access ports
being formed in a retaining element for said valve and being
connected to the passages by unions formed in the case, the
retaining element being removably locked by a ringnut screwed onto
the case; and,
a plate having two portions, each of the portions having an upper
sleeve and a lower sleeve, said upper sleeves being structured to
receive said removal means and said admission means for the blood
and said lower sleeves being structured to penetrate said access
ports, the plate being lockable on the vascular access device by a
shaped ring threadable onto the case.
2. The device of claim 1, further comprising a closing element,
insertable and removable in said device, the closing element having
stoppers designed to penetrate the access ports.
3. The device of claim 2, wherein said closing element is retained
on the device by a cover screwed onto the case after placing
between said element and said cover a layer of disinfecting
material.
4. The device of claim 1, wherein said retaining element has an
opening which surrounds said valve, said opening having on its
surface a convex protrusion designed to snap, upon rotation of the
valve, into notches provided on an edge of said valve at points
designed to fix the device at an angular operating position and at
an angular neutral position.
5. The device of claim 4, wherein rotation of the valve is
accomplished with a set screw wrench inserted in a blind axial hole
made in said valve.
6. The device of claim 1, wherein the access ports are connected to
a blood dialyzer.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention refers to a vascular access device, in
particular for purification treatments of the blood.
2. Prior Art
There are many patients who must submit periodically and with a
certain frequency to blood purification treatments such as
dialysis. For these patients, in order to eliminate the repeated
insertion of needles for taking the blood to be purified and the
inlet of the purified blood, there have been developed recently the
so-called `vascular access` devices which are inserted permanently
in the body of the patient and connected to his blood vessels.
Of this art a certain number of vascular access devices are known
which comprise essentially a hollow body with apertures
communicating with a duct integral therewith, which is grafted onto
a blood vessel (artery or vein). Inside the hollow body there is
housed a valve with passages which in one of its positions
establishes communication between the blood vessel and external
ducts connecting with means for removal and admission of the blood.
By turning the valve said communication is interrupted. Examples of
such devices are described in the patents FR 2571260, U.S. No.
4108174, U.S. No. 4015601, U.S. No. 4108173.
In some cases it was preferred to avoid removal and admission of
the blood in the same zone and a vascular access device was
achieved having two separate ducts inserted in different blood
vessels (an artery and a vein) first connected through a fistule or
bypass produced artificially. Said device is described in patents
U.S. No. 4092983 and U.S. No. 4108174.
The drawback common to all the devices of the known art lies in the
fact that not all the blood arriving in the vessel is routed to the
purification equipment. A non-negligible part goes beyond the
removal zone and mixes with the blood already purified. In
addition, part of the returning blood can be recirculated by
immediate intake back into the dialysis apparatus. As a result the
efficiency of the purification treatment is reduced.
At the same time the formation of artificial fistules always calls
for a surgical operation which it is not always possible to
perform.
Another considerable drawback of said devices consists of the
possible formation of coagulated blood and thrombi in the graft
zone which must be removed quickly to avoid occlusion of the
grafted duct.
Lastly, the need for periodic cleaning and maintenance of the
device without removing said device from the body must be met.
SUMMARY OF THE INVENTION
In view of this state of the art an object of the present invention
is to achieve a vascular access device for performing blood
purification treatments which without requiring the formation of
fistules upstream would allow removal of all the blood arriving
within the blood vessel intercepted, thereby preventing mixing of
the unpurified blood with the blood already purified.
Another object is to provide a vascular access device which would
considerably reduce the possibility of the formation of
thrombi.
Another object is to achieve a vascular access device which would
make possible easy and fast cleaning and maintenance operations
when necessary.
In accordance with the invention these objects are achieved by
making a vascular access device in particular for purification
treatment of the blood comprising a case designed to be grafted
permanently in a living tissue and equipped with a pair of
connections for blood vessels, a 2-position valve housed in said
case and a pair of access openings for means of removal and
admission of the blood. The connections are formed in such a manner
as to couple with respective ends of cut blood vessels and said
valve has two independent passages which in a first position of
said valve establish respectively connection between a first
connection and a first access opening and between the second
connection and the second access opening while in a second position
of the valve they establish respectively the connection between
said first and said second connection and between said first and
said second access opening.
In this manner with the valve in the aforesaid first position the
blood can be taken from a first blood vessel such as an artery or
from an upstream part of a single cut vessel (i.e., a vein or
artery) and made to circulate to the dialysis apparatus to then be
readmitted in a second blood vessel such as a vein or in a
downstream part of said cut single vessel. With the valve in the
second position at the same time one of the two passages of the
valve allows the blood to pass freely from one vessel to the other
or from one part to the other of the single cut vessel, leaving the
possibility of performing cleaning of the passage in the period not
involving blood circulation. The two passages can be reversed for
cleaning of the other passage.
With such an arrangement of the connections in combination with a
2-duct valve there is obtained the removal of all the blood flow
and readmission of the purified blood is effected without
disturbing the normal venous flow.
The efficiency of the purification is increased, no arterial or
venous fistules are required upstream, the formation of thrombi is
made highly improbable, and easy, quick cleaning of the passages
involved in the blood flow is possible for the removal of any
thrombi.
BRIEF DESCRIPTION OF THE DRAWINGS
A possible practical embodiment of the present invention is
illustrated as a nonlimiting example in the annexed drawings
wherein:
FIG. 1 shows a perspective view of the vascular access device in
accordance with the invention in operating position,
FIG. 2 shows a perspective view of said device in the cleaning
phase,
FIG. 3 shows a perspective view of said device in neutral
position,
FIG. 4 shows a horizontal section of said device in the operating
position of FIG. 1 along line IV--IV of FIG. 5,
FIG. 5 shows a vertical section of said device along line V--V of
FIG. 4,
FIG. 6 shows a horizontal section of said device in the position of
FIG. 2 along line VI--VI of FIG. 7,
FIG. 7 shows a vertical section of said device along line VII--VII
of FIG. 6, and
FIG. 8 shows a vertical section of said device in the neutral
position of FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the annexed figures there is shown a vascular
access device comprising a case 1 of rigid biocompatible plastic
material (e.g. Teflon) designed to be grafted permanently in living
tissue 2 (e.g. of an arm) and having two connections 3 and 4 for
two ends 60 and 61 of artificial vessels sutured at 51 and 52 to
blood vessels 5 and 6 respectively, such as an artery and a vein
respectively or two separate parts of a single cut vessel (artery
or vein). Said ends 60 and 61 are fixed to the connections 3 and 4
respectively by means of one or more lock rings 62. The outer
surface of the case 1 is covered with a first layer 9 of rubbery
dampening material (e.g. Silastic) on which is arranged a second
layer of biologically compatible material 10 (e.g. Goretex) capable
of being welded to the human tissue in which the device is
grafted.
For better fixing of the device to the tissue in which it is
grafted the layer of biologically compatible material 10 is fixed
to the underlying muscle with suture stitches 63.
The connections 3 and 4 are in the form of sleeves with an interior
passage 7 presenting a terminal section 8 flaring outward.
The case 1 has a cavity which describes a lower seat having a
circular side wall 11 and a closed bottom 12 and an upper seat
having side walls 13 and a partially open bottom 14. The case 1
comprises also unions 15 and 16 having the lower mouths 17 made in
the side wall 11 of the lower seat and the upper flanged mouths 18
protruding from the bottom 14 of the upper seat (FIG. 5).
Within the lower seat of the case 1 is placed a valve 19 rotating
around an axis perpendicular to the bottom 14 and within the upper
seat 12 is placed a retaining element 20 having an opening 50 which
surrounds part of said valve 19, said element 20 having in addition
vertical passages (21 and 22) arranged in such a manner as to mate
with the upper flared mouths of the unions 15 and 16 of the case
1.
The valve 19, as shown in FIG. 4, has two passages 23 and 24 with
curved axis which form a system of communication between the inner
passages 7 of said connections 3 and 4 of said unions 15 and 16 and
a blind hole 25 for the introduction of a set screw wrench 26
(FIGS. 1 and 2) for operation of said valve.
In the position of FIGS. 4 and 5 the passage 23 connects the
coupling 3 to the union 15 and then to the vertical passage 21 and
the passage 24 connects the connection 4 to the union 16 and then
to the vertical passage 22. In said passages 21 and 22 are
introduced a blood removal catheter 27 and a blood admission
catheter 28 respectively connected to the dialysis apparatus (not
shown). For better application of said catheters 27 and 28 there is
provided a plate 29 to be placed during use over said retaining
element 20 and the valve 19 and having two projecting portions 38,
each forming an upper sleeve 30 and a lower sleeve 31. The upper
sleeves 30 are designed to receive removal catheters 27 and
admission catheters 28 for the blood and the lower sleeves 31 are
designed to penetrate in the vertical passages 21 and 22 of the
retaining element 20 to constitute therewith access ports for said
removal and admission catheters 27 and 28. The plate 29 also has an
opening 32 corresponding with the blind hole 25.
The retaining element 20 is locked in the retaining position of the
valve 19 by means of a ringnut 33 with a ridged or splined contour
54 screwed between the element 20 and the upper edge 34 of the case
1.
In addition, to retain the plate 29 in the operating position there
is provided a shaped ring 35 screwed on the outer side of the edge
34 of the case 1.
Said plate 29 is applied to the retaining element 20 only when
there are performed blood purification treatments (FIGS. 4 and 5)
and subsequent cleaning of the device at the end of purification
(FIG. 2), which is performed by arranging the valve 19 in the
position shown in FIGS. 6 and 7. In other words, by rotating the
valve 19 the passage 23 is brought to the connection position
between the mouths 17 of the unions 15 and 16 simultaneously the
passage 24 arranges itself for connection between the passages 7 of
the connections 3 and 4, thus reestablishing normal blood
circulation.
In order to accurately position the valve 19 there are provided in
the body of the valve four notches 36 arranged at 90.degree. angles
from each other and which are selectively engaged by clips on a
convex protrusion 37 provided on the surface of the opening 50 of
the retaining element 20. Said clip system is useful for fixing the
position of the valve during the blood purifying phase or the
cleaning or neutral phase of the device, preventing any undesired
rotation of the valve.
In the neutral position (FIG. 3) the shaped ring 35 and the plate
29 are removed and in their place are applied to the device a
closing element 39 (FIG. 8), a layer of disinfecting material 40
and a cover 41 screwed, similarly to the shaped ring 35, on the
edge 34 of the case 1. The closing element 39 has plugs 42 designed
to penetrate in the vertical passages 21 and 22 of the retaining
element 20.
The device described is designed to operate as follows.
The patient to whom has been applied the device normally carries
the device in a suitable part of the body, e.g. an arm as shown in
FIG. 3. A connection (3) is preferably coupled in a precise manner
to an end 60 of an artificial vessel sutured at 51 to a section of
artery 5 appropriately cut and the other connection (4) is
preferably coupled in the same manner by means of an end 61 to a
section of vein 6 appropriately cut and reattached at 52. The
arrangement of the parts of the device in neutral position is shown
in FIG. 8, in other words one of the passages 23, 24 of the valve
19 constitutes the artery-vein connection while the other is
inactive and constitutes a connection between the unions 15 and
16.
To proceed with the purification treatment the cover 41, the
disinfecting material 40 and the closing element 39 are removed,
and the plate 29 is applied causing the lower sleeves 31 to
penetrate in the vertical passages 21 and 22 respectively. The
plate is then locked by screwing on the case 1 the shaped ring 35.
Finally, there are introduced in the sleeves 30 removal catheter 27
and admission catheter 28 for the blood (FIGS. 1 and 5). At this
point are performed the connection between the artery 5 and the
blood removal catheter 27 and between the vein 6 and the blood
admission catheter 28 by rotating the valve 19 by 90.degree. so
that its passages 23 and 24 will be arranged as shown in FIGS. 4
and 5.
At the end of the purification phase the valve 19 is rotated again
to interrupt communication of the blood vessels 5 and 6 with the
passages 23 and 24 and hence with the respective unions 15 and 16
and the means 27 and 28 while the artery-vein connection is
restored by, for example, the passage 24 as shown in FIGS. 6 and
7.
The passage 23 can now by cleaned, as it is in position connecting
the unions 15 and 16, by introducing in the upper sleeves 30 of the
plate appropriate cleaning tubes 43 and 44 which clean said duct
23, said unions 15 and 16 and said passages 21 and 22 (FIGS. 2, 6
and 7).
At the end of these operations the shaped ring 35 and the plate 29
are removed and the device is closed by applying the closing
element 39, a new layer of disinfecting material 40 and the cover
41 (FIGS. 1 and 8).
It should be noted that the device described also allows easy
maintenance of the operating parts of said device, in particular of
the valve 19, with no need to remove the entire device and then
reinsert it in the arm of the patient with further surgical
operations.
This is achievable because once the cover 41 is unscrewed and the
layer of disinfecting material and the closing element 39 have been
removed it is also possible to unscrew the ringnut 33 and remove
the retaining element 20 to finally gain access to the valve 19 and
remove it from the case 1, which remains in position in the
patient's arm. Naturally the connected vessels 5 and 6 will have to
be blocked first, for example with an ordinary hemostatic loop.
* * * * *